1. Technical Field
The disclosure relates to a memory management method, and more particularly, relates to a memory management method, a memory storage device and a memory control circuit unit.
2. Description of Related Art
The markets of digital cameras, cellular phones, and MP3 players have expanded rapidly in recent years, resulting in escalated demand for storage media by consumers. The characteristics of data non-volatility, low power consumption, and compact size make a rewritable non-volatile memory module (e.g., flash memory) ideal to be built in the portable multi-media devices as cited above.
Generally, in hybrid mode flash memory, some memory cells are used to store two or three bits (also known as digits thereinafter) per memory cell, and some other memory cells are used to store one single bit per memory cell. For example, some physical blocks are designed to be used for storing two or three bits per memory cell, and some other physical blocks are designed to be used for storing one single bit per memory cell. If some memory cells in one specific physical block have poor reliability and some other memory cells in the same physical block still have well reliability, then, in general case, all memory cells in this physical block are arranged to be used for storing one single bit per memory cell to increase the reliability of this physical block thereby. However, this procedure may cause the waste of data capacity because some memory cells with well reliabilities actually can still be used for storing multiple bits instead. Accordingly, how to design a manner to overcome the physical limitation and improve the reliability of each target memory cell is an important issue in the related technology field.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present disclosure. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present disclosure, or that any reference forms a part of the common general knowledge in the art.